Flour-sifter



J. H. DEAN.

FLOUR SIFTER.

APPLICATION FILED MAY 23, um. 1,395,096, Patented Oct. 25, 1921.

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jmuz/ IzvenZfi- Jimzes 39a UNITED STATES PATENT OFFICE.

JAMES H. DEAN, OF CHICAGO, ILLINOIS.

FLOUR-SIFTER.

Application filed. May 23,

T 0 all whom it may concern:

Be it known that I, JAMns I'I. DEAN, a citizen of the United States, and a resident of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Flour-Sifters, of which the following is a specification.

The improvement relates to flour sifters of the type adapted to be mounted on the hopper bottom of a flour bin such as shown in the prior United States Letters Patent No. 1,369,790, issued to me March 1, 1921.

The present invention seeks to provide an improved, inexpensive construction and more particularly to improve and simplify the construction set forth in the said patent. The invention consists in the features of im* provement and combinations of parts hereinafter set forth, illustrated in the preferred form in the accompanying drawings and more particularly pointed out in the appended claims.

In the drawings Figure 1 is a view in elevation of the im proved sifter with the casing wall broken away.

Fig. 2 is a vertical section on the line 22 of Fig. 1.

Fig. 3 is a detail plan view of a portion of the operating mechanism parts being shown in horizontal section.

The casing 10 of the improved sifter is hopper-like in form, is circular in cross section, has an open top and a contracted bottom portion provided with a discharge opening, the latter being provided with a removable cap 12. The casing hasprojecting ears .11 by which it may be detachably secured to the hopper bottomv of a flour bin. The sifter or sieve-basket comprises a metal rim 13, a dished wire-cloth body 14: and a supporting frame. The supporting frame preferably comprises a transverse metal bar or strip 15 having upturned ends soldered or otherwise suitably secured to the rim 13. The strip 15 has an upwardly bowed central portion 16 of inverted U-shape which supports and bows upwardly the central portion of the wire-cloth body 14c of the sieve-basket. A cross piece 17 is riveted or otherwise secured to the strip 15 on opposite sides of the upwardly bowed central portion thereof and, in the preferred form shown is provided at one end with a downturned ertension 18. The cross piece 17 and the portion 16 are provided with axial bearing Specification of Letters lPatent.

Patented Oct. 25, 1921.

1921. Serial No. 471,890.

openings which are adapted to detachably engage a vertical pivot pin or stud 19 fixed in position within the casing.

In the preferred construction shown the pivot pin is mounted upon the upper portion of a supportingplate 20 which is preferably of inverted U-shape in section and one side of which is riveted or otherwise secured to a transverse bar 21. The latter is arranged on edge and extends diametrically from side to side of the casing 10 and is suitably secured at its ends to the casing wall. IVhen the sieve-basket is in position in the casing the cross piece 17 engages'the upper flat portion of the supporting plate 20 with the pivot pin 19 engaging the bearing openings in the spaced portions 16 and 17 of the basket frame. 'The pivot pin, as shown, can be conveniently formed of a cotter pinand be held in place by a second cotter pin 22. extending transversely through its eye and through the opposite sides of the support 20. The basket is thus mounted in the casing to oscillate about a central vertical axis but can be readily removed when the sifter casing is detached from the flour bin for cleaning the basket and interior of the casing,

The means for oscillating the basket is operated by a rotatable shaft 23 arranged in the casing below the basket. The shaft extends horizontally into the casing and is journaled at its inner end in the support 20 and cross bar 21 and at its outer end in a plate 24 fixed to the casing wall. An external hand crank 25 is provided for rotating the shaft and preferably is formed in piece therewith.

An actuator is interposed between the operating shaft and the basket and is pivotally mounted in the casing to swing in a plane at right angles to the shaft 22, the actuator being detachably connected to the basket to oscillate the same and the shaft having means arranged to engage and opcrate the actuator. As shown the actuator comprises a pair of parallel arms .26 pivotally mounted at their upper ends in the upper portion of the support 20 and connected by a link 27 which is pivotally connectedto their lower ends. The arms 26 are arranged atequal distances on opposite sides of the a-xisof the shaft 23 and are arranged to be engaged and swung back and forth by .acam 28 fixed to the shaft. The link 27 is centrally connected to the frame of the sieve-basket preferably by providing the central portion of the link with a laterally projecting U-shaped off-set 29 which is detachably engaged by the depending extension 18. The extension 18 and the slotted or U-shaped portion 29 form a sliding connection between the actuator and sieve-basket which permits the oscillation of the basketv about a vertical axis and the swinging movement of the actuator in a transverse vertical plane without binding between the connected parts. Moreover it does not interfere with removal or replacing of the sievebasket.

In the preferred construction shown the arms 26 are formed of round metal rods and have bent upper and lower ends forming oppositely projecting journals or pivots 30 and 31. The pivots 30 extend through bearing openings formed in the opposite sides of the U-shaped support 20 and the pivots 31 extend through U-shaped end portions 32 of the connecting link 27. The U-shaped end portions 32 extend around the cam 28 and the pivots 31 form abutments on opposite sides of the axis of the shaft 23 which are arranged to be'engaged by the cam to oscillate the arms 26 and, through the medium of the link 27 and the extension 18, oscillate the basket. The cam 28 is preferably formed of sheet metal and is fixed to the end of a sleeve '33 which fits over the inner end of the shaft 23 and extends through the bearing openings in the transverse bar 21 and in the opposite sides of the U-shaped support 20. A cotter pin 34: extending through the sleeve and shaft hold the latter and the cam 28 in assembled relation, washers 35 being provided between the cotter pin and the sides of the support 20 to take up lost motion. The link 27 has U-shaped ends 32, as stated, which extend around the edges of the cam so that the link is held against displacement by the cam. The link in turn holds the arms 26 against displacement. Thus, with this arrangement, the single cotter pin 34 serves to hold the shaft, cam, link and swinging arms in assembled relation no other fastening means being required for this purpose and hence the parts can be quickly and economically assembled.

For rapidly oscillating the basket the ,cam 28 is star-shaped and has an odd number of cam points 36 which alternately engage the pins or abutments 31 on the lower ends of the arms 26. Preferably five such cam points are provided so that five complete oscillations of the sieve basket are effected for each rotation of the shaft 23 and hand crank 25. To move the actuator and basket in opposite directions at the uniform rate relatively to the speed of op eration of the shaft 23, the cam teeth 36 are provided with 'convexly curved working edges similar in outline to the curved faces of gear teeth. It should be noted that the inner portion of the working face of one tooth strikes one of the abutments 31 to reverse the direction of movement of the actuator and of the basket immediate after the other abutment passes over the outer end of another tooth and, by providing'the teeth with curved working edges as shown, the follower and basket will not be traveling at an excessive rate of speed when their di rection of movement is so reversed and the wear on the cam teeth is not excessive. The points of the star-shaped cam are symmetrical in outline so that the means for operating the basket will operate properly when the hand crank 25 is rotated in either direction.

It should be noted that the spaced members of the supporting plate 20 form extended bearings for the crank shaft 23, cam 23 and the arms 26 of the cam follower or basket actuator so that the axes of the shaft and cam are held in proper alinement and in proper parallel relation with the pivot axes of the arms independently of the wall of'the casing 10 which is usually formed of very thin sheet metal.

Obviously, changes can be made in the details set forth without departure from the essentials of the invention as defined in the claims.

I claim as my invention 1. In a flour sifter, a casing, a vertical pivot stud fixed therein, a sieve-basket in the upper portion of said casing comprising a dished wire-cloth body having a metal rim, a transverse supporting frame having upturned ends fixed to said rim and an upwardly projecting central portion supporting and bowing upwardly the central portion of the wire-cloth body, the central portion of said frame comprising spaced upper and lower members having axial bearing openings engaging said pivot stud, and means in said casing engaging saidsupporting frame for oscillating the basket.

2. In a flour sifter, a casing, a vertical pivot stud fixed therein, a sieve-basket in the upper portion of said casing comprising a dished wire-cloth body having a metal rim, a transverse supporting strip having upturned ends secured to said rim and an upwardly bowed central portion supporting and bowing upwardly the central portion of the wire-cloth body, a cross-piece having a downturned extension connected to said strip on opposite sides of the upwardly bowed central portion thereof, the latter and,

said cross-piece having axial bearing openings detachably engaging said stud, and means in said casing detachably engaging said extension for oscillating the basket.

7 3. A flour sifter comprising a hopper-like. casing adapted to be detachably secured to the lower end of a flour bin, a sieve-basket removably mounted in said casing to oscillate about a central vertical axis, a horizontal shaft rotatably mounted in said casing below the basket, and an actuator pivotall mounted in said casing to swing back ant forth in a vertical plane at right angles to said shaft, and having a detachable connection with said basket to oscillate the same, said shaft having operating means for said actuator.

4-. A flour sifter comprising a hopper-like casing, a sieve-basket mounted therein to oscillate about a central vertical axis, a horizontal shaft rotatably mounted in said casing below the basket, an actuator pivotally mounted in said casing to swing back and forth in a vertical plane at right angles to said shaft, and having a sliding connection with said basket to oscillate the same, said shaft having means operatively engaging said actuator and an external hand crank for rotating said shaft.

5. A flour sifter comprising a hopper-like casing, a sieve-basket removably mounted therein, a horizontal rotatable shaft extending into said casing below the basket and having a hand crank on its outer end, an actuator pivotally mounted in said casing to swing back and forth in a vertical plane at right angles to said shaft, and havin a detachable connection with said sieve-has ret to oscillate the same, and a cam on said shaft having a plurality of symmetrical cam points operatively engaging said actuator.

6. A flour sifter comprising a hopper-like casing, a sieve'basket removably mounted therein to oscillate about a central vertical axis, a horizontal, rotatable shaft extending into said casing below the basket, and having a hand crank on its outer end, an actuator pivotally mounted in said casing to swing back and forth in a vertical plane at right angles to said shaft, said actuator hav ing abutments on opposite sides of the axis of said shaft and having a detachable sliding connection with said basket at a point midway between said abutments, and a starshaped cam on said shaft having an odd number of symmetrical teeth arranged to alternately engage said abutments.

7. A flour sifter comprising a casing, a sieve-basket removably mounted therein, a rotatable shaft in said casing below the basket, a pair of arms pivotally mounted in said casing on opposite sides of the axis of said shaft, a connecting link pivoted to said arms and detachably connected to said basket, a cam on said shaft for positively oscillating said arms, and an external hand crank for rotating said shaft.

8. A flour sifter comprising a casing, a sieve-basket removably mounted therein to oscillate about a central vertical axis, a rotatable shaft in said casing below the basket, a pair of parallel arms pivotally mounted in said casing on opposite sides of the axis of said shaft, a link connecting said arms and having a central detachable connection with said basket, and a cam on said shaft arranged to engage and positively oscillate said arms.

9. A flour sifter comprising a hopper-like casing, a sieve-basket removably mounted therein to oscillate about a vertical axis, a horizontal shaft rotatably mounted in said casing below the basket, a pair of vertically disposed arms pivotally mounted in said cas-' ing on opposite sides of said shaft, a link pivotally connected to said arms and having a central detachable connection with said basket, and a cam on said shaft for oscillating said arms. V

10. A flour sifter comprising a hopperlike casing, a sieve-basket removably mounted therein, a rotatable, horizontal shaft journaled in said casing below the basket and having a hand crank on its outer end, a pair of vertically disposed arms pivotally mounted in said casing on opposite sides of said shaft, a link connecting said arms and detachably connected to said basket, and a star-shaped cam having an odd number of teeth arranged to alternately engage and positively oscillate said arms.

11. A flour sifter comprising a casing, a transverse support therein, an oscillating sieve-basket removably mounted on said support, a rotatable shaft journaled in said support, a cam on said shaft, a pair of arms on opposite sides of said cam, a link connecting said arms and detachably connecting the same to said basket, said link extending across the face of said cam and having U-shaped end extending about the edges thereof, said arms having pivot pins removably engaging said support and the ends of said link, and means for connecting said cam and shaft and for holding the same in position, said cam cooperating with the Ushaped ends of said link to hold the latter and said arms in position, substantially as described.

12. A flour sifter comprising a casing, a transverse support therein comprising spaced members, a sieve-basket removably mounted on said support to oscillate about a vertical axis, a horizontal shaft having a hand crank on its outer end, and journaled at its inner end in said spaced members, a multi-point cam on the inner end of said shaft having a sleeve pinned to said shaft between said members, a pair of vertical disposed arms having lateral projecting pivot pins engaging said spaced members and opposite projecting pins or abutments on opposite sides of said cam, and a link having a central detachable connection with said basket and engaging said last-mentioned pivot pins to hold the same in operative relation with said cam, substantially as described.

13. A flour Sifter comprising a casing of thin sheet metal, a sieve-basket therein adapted to oscillate about a centralvertical axis, a rotatable shaft extending horizontally into said casing, a cam on said shaft below the basket, a follower for said cam connected to said basket, a support extending transversely from side to side of said casing having an extended bearing for holding said cam and cam shaft in alinement and whereon said basket and follower are mounted, and means cooperating with said support for holding said cam and shaft in assembled relation and against endwise movement.

14:- A flour sifter comprising a sheet metal casing, a transverse support of inverted U-shape mounted in said casing, a vertical stud centrally fixed to the upper portion of said support, a sieve-basket having a frame removably engaging said stud and provided with a depending part, a horizontal shaft having a hand crank on its outer end and journaled at its inner end in the spaced members of said U-shaped support, a cam on the inner end of said shaft, a pair of arms having pivots at their upper ends journaled in'said spaced members and having'pins at their lower ends adapted to be engaged by said cam, a link engaging said lower pins and detachably engagingthe dependingpart of the basket frame, and means connecting said cam and shaft and cooperating with said support to hold said parts against axial movement.

15. A flour Sifter comprising a casing, a sieve basket mounted therein to oscillate about a central vertical axis, a pair of arms pivotally mounted in said casing on opposite sides of the axis of said basket, a link pivoted to said arms and connected to said basket, a rotatable, multi-pointed cam in said casing for positively, moving said arms in opposite directions to thereby oscillate said basket and an external hand crank for rotating said cam.

' JAMES H. DEAN. 

